std::error_category

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std::error_category
Member functions error_category::error_category error_category::~error_category error_category::name error_category::default_error_condition error_category::equivalent error_category::message error_category::operator== error_category::operator!= error_category::operator<

Defined in header <system_error>
class error_category;		(since C++11)

std::error_category serves as the base class for specific error category types, such as system_category, iostream_category, etc. Each specific category class defines the error_code - error_condition mapping and holds the explanatory strings for all error_conditions. The objects of error category classes are treated as singletons, passed by reference.

[edit] Member functions

(constructor)	constructs an error_category (public member function)
(destructor) [virtual]	destructs an error_category (virtual public member function)
operator=	the assignment operator is deleted (public member function)
name [virtual]	obtains the name of the category (virtual public member function)
default_error_condition [virtual]	maps error_code to error_condition (virtual public member function)
equivalent [virtual]	compares error_code and error_condition (virtual public member function)
message [virtual]	obtains the explanatory string for error_condition (virtual public member function)
operator== operator!=	compares error_categories (function)
operator<	provides ordering for error_categories (function)

[edit] Specific error categories

generic_category (C++11)	identifies the generic error category (function)
system_category (C++11)	identifies the operating system error category (function)
iostream_category (C++11)	identifies the iostream error category (function)
future_category (C++11)	identifies the future error category (function)

[edit] See also

error_condition (C++11)	holds a portable error code (class)
error_code (C++11)	holds a platform-dependent error code (class)